LG Multi V 5 - Check Valve (Outdoor EEV Check Valve); Check Valve (Oil Separator)

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_TROUBLE SHOOTING GUIDE BOOK _
5. 4Way Valve
1. Keep it off before the outdoor unit is powered on and the indoor unit is turned on.
2. Cooling, defrosting, oil recovery : OFF, heating : ON
3. When alternating cooling to heating, transform 4 way valve during re-starting for 3 minutes.
4. To check the mode of cooling/heating operation of 4 way valve, touch the piping surface of low pressure
service valve.
5. Refrigerant flowchart of 4 way valve
6. Insulation resistance in the state of connecting the valve to coil should be over 100mΩ when measure it
with DC mega tester(DC 500V).
■ Checking Method (Flow Chart)
After 3 minutes
operating, the difference
between the high and low
pressure is more than 4
atm?
The compressor is
operating normally?
The connection of PCB
terminal is correct?
Voltage is applied
successfully on the PCB?
After 3 minutes
operating, the difference
between the high and low
pressure is more than 4
atm?
Replace the compressor
Re-connection of PCB terminal
Replace the PCB
Check the 4 way valve coil and
replace
Restart (after operating the self-
recovery logic of 4 way valve in
case of series)
Checking start
No malfunction of 4 way valve
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
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Only for training and service purposes
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Checking Method for Key Components
2.11 Reverse Valve
2.12 Temperature Sensor
1. Keep it off before the outdoor unit is powered on and the indoor unit is turned on.
2. Cooling, defrosting, oil recovery : OFF, heating : ON
3. When alternating cooling to heating, transform 4 way valve during re-starting for 3 minutes.
4.
To check the mode of cooling/heating operation of 4 way valve, touch the piping surface of low pressure service valve.
5. Refrigerant flowchart of 4 way valve
6. Insulation resistance in the state of connecting the valve to coil should be over 100mΩ when measure it with DC
mega tester(DC 500V).
1) outdoor temperature sensor : TH1
2) Pipe temperature sensor : TH2
3) Discharge pipe(D-pipe) temperature sensor : TH3
1. Check the condition of installation and the contact of temperature sensor.
2. Check whether the connector contact of temperature sensor is normal.
3. Measure the resistance of temperature sensor.
Resistance
TH1
10KΩ±1%(25℃)
1.07KΩ±3.3%(85℃)
5KΩ±1%(25℃)
535KΩ±3.3%(85℃)
200KΩ±1%(25℃)
28KΩ±7.7%(85℃)
TH2 TH3
[Heating Operation]
Outdoor Heat
Exchanger
Outdoor Heat
Exchanger
D : Discharge
E : Evaporator
C : Condensor
S : Suction
Indoor Heat
Exchanger
[Cooling Operation]
6. Check Valve (Outdoor EEV Check Valve)
7. Check Valve (Oil Separator)
There is a temperature
difference across the check
valve during the cooling
operation?
There is a temperature
difference between
front and rear of the outdoor
EEV during full heating
operation?
Outdoor EEV is correct?
Replace the outdoor EEV
Replace the check valve
Replace the check valve
Checking start
No malfunction of check valve
Yes
Yes
Yes
No
No
No
No
In normal condition of
compressor discharging
temperature, there is the
temperature difference of
check valve?
Replace the check valve
Checking start
No malfunction of check valve
Yes
No
Basic Part
Multi V 5
Intorduction
Trouble Shooting
Function Control
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